Size of RSJ to replace a kitchen/Living room wall?

[TheWife]

As I understand it...its length will be 5metres....but I dont know what depth/width/weight it should be, any one help? And are they expensive?
Do I need to go through a solicitor / planning office to pu an RSJ in? Or can I just seek agreement from my neighbours should they be affected by it. I believe that what was used to be done until someone mentioned that they think the rules around RSJ's have changed...is this true?

 

[masona]

Go down to your local planning control department and they will tell you there and then.In my area you don't have to make a appointment and they are very helpful.

 

[Building Contractor]

You will need a structual engineer to determine what size beam you need, 5m is quite a bit to take out, be very careful of what you are doing, it a job for an experienced contractor and not the DIY